Alzheimer’s Disease Biomarker Panel, Cerebrospinal Fluid
Test Mnemonic
ALZCSF
CPT Codes
- 83520 - QTY (3)
Aliases
- Alzheimer’s Disease Core Biomarkers, Cerebrospinal Fluid
- Alzheimer’s Disease Biomarkers Phospho-Tau(181P) / Total-Tau / A Beta42 / Phospho-Tau(181P) Ratio / Total-Tau Ratio
- Alzheimer’s Disease Biomarkers Phospho-Tau(181P) / Total-Tau / A Beta42 / Phospho-Tau(181P) Ratio / Total-Tau Ratio, Analysis and Interpretation
Performing Laboratory
Cleveland Clinic Laboratories
Specimen Requirements
| Volume | Type | Container | Collect Temperature | Transport Temperature | Special Instructions |
|---|---|---|---|---|---|
| 2.5 mL | Cerebrospinal fluid (CSF) | See note | Refrigerated | Collection and transport MUST be done in the approved polypropylene CSF tube (Sarstedt CSF False Bottom Tube, Ref 63.614.625). Other tubes for collection and transport are not acceptable. Do NOT transfer or aliquot the CSF sample. NOTE: Do not use the first 2 mL of CSF collection for this test. |
Minimum Specimen Requirements
| Volume | Type | Container | Collect Temperature | Transport Temperature | Special Instructions |
|---|---|---|---|---|---|
| 2.5 mL |
Stability
| Environmental Condition | Description |
|---|---|
| Ambient | 5 days |
| Refrigerated | 14 days |
| Frozen | 8 weeks NOTE: Do NOT freeze at < -60 C. |
Days Performed
1 day per week
Turnaround Time
1 - 8 days
Methodology
| Name | Description |
|---|---|
| Electro Chemiluminescence Immunoassay (ECLIA) |
Reference Range
| Abeta42 | |||||
|---|---|---|---|---|---|
| Sex | Age From | Age To | Type | Range | Range Unit |
| Normal | >= 564.2 | pg/mL | |||
| Phospho-Tau (181P) | |||||
| Sex | Age From | Age To | Type | Range | Range Unit |
| Normal | <= 31.30 | pg/mL | |||
| Phospho-Tau (181P) / Abeta42 ratio | |||||
| Sex | Age From | Age To | Type | Range | Range Unit |
| Normal | <= 0.0230 | ||||
| Total-Tau | |||||
| Sex | Age From | Age To | Type | Range | Range Unit |
| Normal | <= 375.4 | pg/mL | |||
| Total-Tau / Abeta42 ratio | |||||
| Sex | Age From | Age To | Type | Range | Range Unit |
| Normal | <= 0.280 |
Special Info
Low-binding polypropylene tubes (Sarstedt, Ref 63.614.625) MUST be used for this test. CSF samples that are collected or transported to the testing laboratory in any other tube are not acceptable and will be rejected. CSF samples that are underfilled will be rejected. Samples that are visibly hemolyzed are not acceptable.
Clinical Info
This test is intended for adult patients aged 55 years and older being evaluated for Alzheimer's disease (AD) and other causes of cognitive impairment.
Clinical Limitation
A positive pTau181/Abeta42 or tTau/Abeta42 ratio result in CSF does not establish a diagnosis of Alzheimer's disease (AD) and should always be interpreted in conjunction with clinical information. The performance of the test for African-American, Asian, and other races had high uncertainty due to the limited number of patients studied. Results should not be used for predicting development of dementia or other neurologic conditions or for monitoring responses to therapies.